The specimen core supports all activities of the UCSD SPOTRIAS site, and the SPOTRIAS national network, by arranging for the collection, storage, and shipment of specimens from patients with acute stroke, TIA, and mimic conditions. Specific Aim 1 continues our routine procedures to obtain, process, and store blood specimens from acute patients at multiple time points. We have established blood-drawing protocols in the emergency departments, intensive care units, and general wards at our collaborating sites. A number of procedures ensure quality handling and labeling of all SPOTRIAS specimens. Specific Aim 2 proposes to derive a panel of serum markers designed to help predict future ischemic events after transient ischemic attack (TIA). It is important to attempt to stratify TIA patients into high- and low-risk groups, and neither the ABCD2 model nor serum biomarkers has been prospectivelv validated for this purpose. We will derive a multi-marker panel that shows good predictive value for estimating subsequent stroke risk, and then compare the predictive value of the derived biomarker panel to the ABCD2 method. After consent, blood samples will be drawn as soon as practical after admission of TIA patients. Blood will be shipped to Biosite, Inc., for assay. The primary endpoint will be the 90-day incidence of new stroke after TIA. Secondary endpoints will be the 90-day NIHSS and modified Rankin Scale. We will also compute an ABCD2 prediction for each patient. We expect the clinical estimate, ABCD2, to predict subsequent stroke risk with reasonable predictive value. We expect to be able to derive a multi-marker panel of biomarkers that also has a reasonable AUC for the ROC curve. We will determine whether either method is superior to the other.